/* DWARF 2 Expression Evaluator.
- Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008, 2009, 2010, 2011
- Free Software Foundation, Inc.
+ Copyright (C) 2001-2003, 2005, 2007-2012 Free Software Foundation,
+ Inc.
Contributed by Daniel Berlin (dan@dberlin.org)
/* Decode the unsigned LEB128 constant at BUF into the variable pointed to
by R, and return the new value of BUF. Verify that it doesn't extend
- past BUF_END. */
+ past BUF_END. R can be NULL, the constant is then only skipped. */
const gdb_byte *
read_uleb128 (const gdb_byte *buf, const gdb_byte *buf_end, ULONGEST * r)
break;
shift += 7;
}
- *r = result;
+ if (r)
+ *r = result;
return buf;
}
/* Decode the signed LEB128 constant at BUF into the variable pointed to
by R, and return the new value of BUF. Verify that it doesn't extend
- past BUF_END. */
+ past BUF_END. R can be NULL, the constant is then only skipped. */
const gdb_byte *
read_sleb128 (const gdb_byte *buf, const gdb_byte *buf_end, LONGEST * r)
if (shift < (sizeof (*r) * 8) && (byte & 0x40) != 0)
result |= -(((LONGEST) 1) << shift);
- *r = result;
+ if (r)
+ *r = result;
return buf;
}
\f
return result;
}
+/* If <BUF..BUF_END] contains DW_FORM_block* with single DW_OP_reg* return the
+ DWARF register number. Otherwise return -1. */
+
+int
+dwarf_block_to_dwarf_reg (const gdb_byte *buf, const gdb_byte *buf_end)
+{
+ ULONGEST dwarf_reg;
+
+ if (buf_end <= buf)
+ return -1;
+ if (*buf >= DW_OP_reg0 && *buf <= DW_OP_reg31)
+ {
+ if (buf_end - buf != 1)
+ return -1;
+ return *buf - DW_OP_reg0;
+ }
+
+ if (*buf == DW_OP_GNU_regval_type)
+ {
+ buf++;
+ buf = read_uleb128 (buf, buf_end, &dwarf_reg);
+ buf = read_uleb128 (buf, buf_end, NULL);
+ }
+ else if (*buf == DW_OP_regx)
+ {
+ buf++;
+ buf = read_uleb128 (buf, buf_end, &dwarf_reg);
+ }
+ else
+ return -1;
+ if (buf != buf_end || (int) dwarf_reg != dwarf_reg)
+ return -1;
+ return dwarf_reg;
+}
+
+/* If <BUF..BUF_END] contains DW_FORM_block* with just DW_OP_breg*(0) and
+ DW_OP_deref* return the DWARF register number. Otherwise return -1.
+ DEREF_SIZE_RETURN contains -1 for DW_OP_deref; otherwise it contains the
+ size from DW_OP_deref_size. */
+
+int
+dwarf_block_to_dwarf_reg_deref (const gdb_byte *buf, const gdb_byte *buf_end,
+ CORE_ADDR *deref_size_return)
+{
+ ULONGEST dwarf_reg;
+ LONGEST offset;
+
+ if (buf_end <= buf)
+ return -1;
+ if (*buf >= DW_OP_breg0 && *buf <= DW_OP_breg31)
+ {
+ dwarf_reg = *buf - DW_OP_breg0;
+ buf++;
+ }
+ else if (*buf == DW_OP_bregx)
+ {
+ buf++;
+ buf = read_uleb128 (buf, buf_end, &dwarf_reg);
+ if ((int) dwarf_reg != dwarf_reg)
+ return -1;
+ }
+ else
+ return -1;
+
+ buf = read_sleb128 (buf, buf_end, &offset);
+ if (offset != 0)
+ return -1;
+
+ if (buf >= buf_end)
+ return -1;
+
+ if (*buf == DW_OP_deref)
+ {
+ buf++;
+ *deref_size_return = -1;
+ }
+ else if (*buf == DW_OP_deref_size)
+ {
+ buf++;
+ if (buf >= buf_end)
+ return -1;
+ *deref_size_return = *buf++;
+ }
+ else
+ return -1;
+
+ if (buf != buf_end)
+ return -1;
+
+ return dwarf_reg;
+}
+
+/* If <BUF..BUF_END] contains DW_FORM_block* with single DW_OP_fbreg(X) fill
+ in FB_OFFSET_RETURN with the X offset and return 1. Otherwise return 0. */
+
+int
+dwarf_block_to_fb_offset (const gdb_byte *buf, const gdb_byte *buf_end,
+ CORE_ADDR *fb_offset_return)
+{
+ LONGEST fb_offset;
+
+ if (buf_end <= buf)
+ return 0;
+
+ if (*buf != DW_OP_fbreg)
+ return 0;
+ buf++;
+
+ buf = read_sleb128 (buf, buf_end, &fb_offset);
+ *fb_offset_return = fb_offset;
+ if (buf != buf_end || fb_offset != (LONGEST) *fb_offset_return)
+ return 0;
+
+ return 1;
+}
+
+/* If <BUF..BUF_END] contains DW_FORM_block* with single DW_OP_bregSP(X) fill
+ in SP_OFFSET_RETURN with the X offset and return 1. Otherwise return 0.
+ The matched SP register number depends on GDBARCH. */
+
+int
+dwarf_block_to_sp_offset (struct gdbarch *gdbarch, const gdb_byte *buf,
+ const gdb_byte *buf_end, CORE_ADDR *sp_offset_return)
+{
+ ULONGEST dwarf_reg;
+ LONGEST sp_offset;
+
+ if (buf_end <= buf)
+ return 0;
+ if (*buf >= DW_OP_breg0 && *buf <= DW_OP_breg31)
+ {
+ dwarf_reg = *buf - DW_OP_breg0;
+ buf++;
+ }
+ else
+ {
+ if (*buf != DW_OP_bregx)
+ return 0;
+ buf++;
+ buf = read_uleb128 (buf, buf_end, &dwarf_reg);
+ }
+
+ if (gdbarch_dwarf2_reg_to_regnum (gdbarch, dwarf_reg)
+ != gdbarch_sp_regnum (gdbarch))
+ return 0;
+
+ buf = read_sleb128 (buf, buf_end, &sp_offset);
+ *sp_offset_return = sp_offset;
+ if (buf != buf_end || sp_offset != (LONGEST) *sp_offset_return)
+ return 0;
+
+ return 1;
+}
+
/* The engine for the expression evaluator. Using the context in CTX,
evaluate the expression between OP_PTR and OP_END. */
goto no_push;
case DW_OP_GNU_entry_value:
- /* This operation is not yet supported by GDB. */
- ctx->location = DWARF_VALUE_OPTIMIZED_OUT;
- ctx->stack_len = 0;
- ctx->num_pieces = 0;
- goto abort_expression;
+ {
+ ULONGEST len;
+ int dwarf_reg;
+ CORE_ADDR deref_size;
+
+ op_ptr = read_uleb128 (op_ptr, op_end, &len);
+ if (op_ptr + len > op_end)
+ error (_("DW_OP_GNU_entry_value: too few bytes available."));
+
+ dwarf_reg = dwarf_block_to_dwarf_reg (op_ptr, op_ptr + len);
+ if (dwarf_reg != -1)
+ {
+ op_ptr += len;
+ ctx->funcs->push_dwarf_reg_entry_value (ctx, dwarf_reg,
+ 0 /* unused */,
+ -1 /* deref_size */);
+ goto no_push;
+ }
+
+ dwarf_reg = dwarf_block_to_dwarf_reg_deref (op_ptr, op_ptr + len,
+ &deref_size);
+ if (dwarf_reg != -1)
+ {
+ if (deref_size == -1)
+ deref_size = ctx->addr_size;
+ op_ptr += len;
+ ctx->funcs->push_dwarf_reg_entry_value (ctx, dwarf_reg,
+ 0 /* unused */,
+ deref_size);
+ goto no_push;
+ }
+
+ error (_("DWARF-2 expression error: DW_OP_GNU_entry_value is "
+ "supported only for single DW_OP_reg* "
+ "or for DW_OP_breg*(0)+DW_OP_deref*"));
+ }
case DW_OP_GNU_const_type:
{
gdb_assert (ctx->recursion_depth >= 0);
}
-/* Stub dwarf_expr_context_funcs.read_reg implementation. */
-
-CORE_ADDR
-ctx_no_read_reg (void *baton, int regnum)
-{
- error (_("Registers access is invalid in this context"));
-}
-
/* Stub dwarf_expr_context_funcs.get_frame_base implementation. */
void
error (_("Support for typed DWARF is not supported in this context"));
}
+/* Stub dwarf_expr_context_funcs.push_dwarf_block_entry_value
+ implementation. */
+
+void
+ctx_no_push_dwarf_reg_entry_value (struct dwarf_expr_context *ctx,
+ int dwarf_reg, CORE_ADDR fb_offset,
+ int deref_size)
+{
+ internal_error (__FILE__, __LINE__,
+ _("Support for DW_OP_GNU_entry_value is unimplemented"));
+}
+
void
_initialize_dwarf2expr (void)
{
projects / external / binutils.git / blobdiff